
Materials and equipment to be supplied by user:
Tabletop microcentrifuge
Nuclease-free 1.5ml microcentrifuge tubes
Water bath capable of 37℃
Shaking water bath capable of 55℃
Incubator or water bath capable of 65℃
100% ethanol
Isopropanol
TE buffer
Vortexer
Before starting
Prepare DNA wash buffer.HBC buffer and lysozyme as instructed in the “preparing reagents” section on page 4
Set an incubaor or water bath to 65℃
Set a water bath to 37℃
Set a shaking water bath to 55℃
Heat elution buffer to 65℃
1.culture bacteria in LB media to log-phase.(overnight culture can be used in many cases)
2.Centrifuge no more than 3ml culture or 1×109 cells at 4000×g for 10 minutes at room temperature
3.Aspiate and discard the media
4.Add 100μL TE buffer . vortex to complete resuspend the pellet
5.Add 10 μL lysozyme
6.Incubate at 37℃ for 10 minutes
Note: the amount of enzyme required and/or the length of incubation may need to be modified depending on the bacterial strain used.complete digestion of the cell wall is essential for efficient lysis.longer incubation time may yield better result.
Optional:follow the short protocol belowfor difficult to lyse bacteria.
1.add 25mg glass beads to 1.5ml microcentrifuge tube.
2.Add sample to the glass beads
3.Vortex at maximum speed for 5 minutes
4.Let sample stang to allow the beads to settle
5.Transfer supernatant to a new 1.5ml microcentrifuge tube.
7.Add 100μL BTL buffer and 20μLProteinase K Solution.vortex to mix thoroughly.
8.incubate at 55℃ in a shaking water bath.
Note:usually no more than 1 hour is required for bacterial lysis.if a shaking water bath is not available,incubate the samples and shake or briefly vortex every20-30minutes.
9.Add 5μL RNase A.INVERT TUBE SEVERAL TIMES TO MIX
10.Incubate at room temperature for 5 minutes
11.Centrifuge at 10000×g for 2 minutes to pellet any undigested material
12.Transfer the supernatan to a new 1.5ml microcentrifuge tube.do not disturb the pellet
13.Add 220μL BDL buffer . votex to mix
14.Incubate at 65℃ for 10 minutes
Note:a wispy precipitate may from upon addition of BDL buffer;it does not interfere with DNA recovery
15.add 220μL 100% ethanol.vortex for 20 seconds at maximum speed to mix thoroughly.
Note:if any precipitate can be seen at this point,break the precipitate by pipetting up ang down 10 times.
16.insert a HiBind DNA Mini Column into a 2ml Collection Tube
17.Transfer the entire sample to the HiBind DNA Mini Column,including any precipitate that may have formed.
18.C×g for 1 minute
19.Discard the filtrate and the collection tube
20. insert a HiBind DNA Mini Column into a new 2ml Collection Tube
21.Add 500μLHBC buffer
Note:HBC buffer must be diluted with isopropanol before use .please see page 4 for instructions
22. ×g for 1 minute
23.Discard the filtrate and reuse the collection tube
24.Add 700μL DNA wash buffer.
Note:DNA Wash Buffer must be diluted with 100% ethanol before use.please see page 4 for instructions.
25.C×g for 1 minute
26.Discard the filtrate and reuse the collection tube
27.repeat steps 24-26 for a second DNA Wash Buffer wash step
28.Centrifuge the empty HiBind DNA Mini Column at maximum speed (>10000×g) for 2 minutes to dry the column
NOTE:this step is criticalfor removal of trace ethanol that may interfere with downstream applications
29.insert a HiBind DNA Mini Column into a new nuclease-free 1.5ml microcentrifuge tube
30.Add50-100μL Elution Buffer heated 65℃ to the HiBind DNA Mini Column
NOTE: make a sure to add the elution buffer to the center of the HiBind matrix.each 50-100 μLelution typically yield 60-70%of the DNA bound to the HiBind matrix.two elutions generally yield~90%. however,increasing elution volume reduces the concentration of the final product .to obtain DNA at higher concentrations ,elution can be carried out using 50μL Elution buffer (which slightly reduces overall DNA yield)volumes lower than 50μLgreatly reduce yields.
31.let sit for 3 to 5 minutes at room temperature
NOTE:yield may be increased by incubating the column at 65℃ (rather than at room temperature) .
32.C×g for 1 minute to elution the DNA
33.Repeat steps 30-32 for a second elution step
34.Store eluted DNA at -20℃.
该方法可从3ml LB培养物中分离细菌基因组
实验者需要的材料和设备:
台式微量离心机
无核酸酶的1.5ml离心管
(水浴锅)水浴温度37℃
震荡的55℃的水浴
恒温箱或65℃的水浴
100%乙醇
异丙醇
TE缓冲液
涡流混合器
实验开始之前
按照第4页的“制备试剂”一节中的说明准备DNA洗涤缓冲液,HBC缓冲液和溶菌酶
设置恒温器或水浴至65℃
设置一个水浴到37℃
摇动水浴至55℃
加热洗脱缓冲液至65℃(Elution Buffer)
1.将LB培养基中的细菌培养至对数期(许多情况下过夜培养可用)
2.在室温下4000×g离心10分钟(培养基不超过3ml或1×109细胞)
3.吸弃上清
4.加入100μL TE缓冲液。涡旋重悬
5.加入10μL溶菌酶
6. 37℃水浴10分钟
注意:所需的酶量和/或水浴时间可能需要根据所使用的细菌菌株进行修改。细胞壁的完全消化对于有效的裂解是必不可少的。更长的温育时间可以产生更好的结果。
可:按照以下简短的方案处理难以裂解细菌。
1.将25mg玻璃珠(破细胞)加入1.5ml离心管中。
2.将样品加入离心管
3.以最大速度涡旋5分钟
4.让珠子沉淀下来
5.将上清液转移到新的1.5ml离心管中。
7.加入100μL BTL缓冲液和20μL蛋白酶K溶液涡旋混匀。
8.置在55℃振荡水浴中。
注意:细菌溶解通常不超过1小时。如果没有摇动的水浴,每20-30分钟摇动或短暂涡旋。
9.加入5μL RNase A。颠倒试管几次混匀
10.室温5分钟
11. 10000×g离心2分钟,沉淀未溶解的物质
12.将上清液转移到新的1.5mL 离心管中,不要搅动沉淀
13.加入220μL BDL缓冲液。 涡旋混合
14.65℃10分钟
注意:加入BDL缓冲液后可能会产生细小的沉淀;它不会干扰DNA的回收
15.加入220μL 100%乙醇,最大速度涡旋混合20秒钟,使重悬充分
注意:如果在这一点上可以看到任何沉淀物,可以通过反复吹打来破坏沉淀。
16.将一个 DNA微柱插入2ml收集管中(2mL collection tube)
17.将整个样品转移至 DNA Mini Column,包括可能形成的沉淀物。
18. 10000×g离心1分钟
19.弃去滤液和收集管
20.将 DNA Mini柱插入新的2ml收集管中
21.加入500μL HBC缓冲液
注意:HBC缓冲液在使用前必须用异丙醇稀释,请参阅第4页的说明
22. 10000×g离心1分钟
23.弃去滤液,依旧使用该收集管
24.加入700μL DNA洗涤缓冲液。(DNA wash buffer)
注意:DNA Wash Buffer必须在使用前用100%乙醇稀释,请参阅第4页的说明。
25. 10000×g离心1分钟
26.弃去滤液并重复使用收集管
27.对于第二次DNA洗涤缓冲液洗涤,步骤重复步骤24-26
28.将空的DNA Mini Column最大速度(> 10000×g)离心2分钟,使柱干燥
注意:这一步对于去除可能干扰下游应用的痕量乙醇是至关重要的
29.将 DNA Mini Column插入一个新的1.5ml离心管中
30.加50-100μL的加热到65℃的 Elution Buffer 到 DNA 微柱
注意:确保将洗脱缓冲液添加到 matrix的中心。每次50-100μL洗脱通常收获 与matrix结合的DNA的60-70%。两次洗脱通常产生约90%。然而,增加洗脱体积会降低最终产物的浓度。为获得更高浓度的DNA,可以使用50μL洗脱缓冲液(其稍微降低总DNA提取量)体积低于50μL进行洗脱,大大降低产量。
31.在室温下静置3至5分钟
注意:通过在65℃(而不是在室温下)可以增加产量。
32.以10000×g离心1分钟
33.重复步骤30-32进行第二次洗脱
34.在-20℃下保存DNA。
这里g是重力加速度,RCF(relative centrifugal field)表示相对离心场,以重力加速度g(/s2)的倍数来表示;rpm(revolution per minute,或r/min)表示离心机每分钟的转数。rmp与g之间的换算公式为:
RCF = 1.119 x 10-5 x (rpm)2 x r
其中r 表示离心机转轴中心与离心管中心的距离,单位为cm。由于离心管的位置由转子(rotor)决定,因此r 必须由查阅相关转子的参数而得。
用binding buffer是为了增加洗脱柱对核酸的结合活性;wash solution是洗掉柱子里除核酸物质以外的杂质;而elution buffer就是最后把DNA从柱子上洗脱下来使用的溶液,一般是pH=8.0的TE,dd水也可以。
预热后,吸附在膜上的DNA可以更充分的溶解。另外一般要求加完Elution Buffer后,静止2-3min,也是为了充分洗脱。
